Thread guide roller

ABSTRACT

A thread guide roller provided with a radially projecting circumferential bead intermediate the ends of its cylindrical thread contacting surface, particularly in combination with a godet in draw-twist apparatus.

UIlitd States Patent" U 1 A Klementi'e't al.

[1'11 3,708,969 74s] Jan. '9, 1973 THREAD GUIDE ROLLER Inventors: PeterKlementz, Hertenweg 77, Er-

lenback; Heinz Massat, Bergerheide 125,- p Wuppertal-Elberfeld;Chrostoph Nit schke, Schlesierstr 9; Herbert Haubold, Schlesierstr 5,both of Obernburg, all of Germany Filed: Oct. 20, 1970 Appl. N01: 82,312

Foreign Application Priority Data Oct. 24, 1969 Germany ..P 19 53 527.4

U.s'. 'cl. I ...s 7/ss.s, 57/106, 2 42/4708 lnt, Cl..'.l ..DOZ1l/22Field of Search .....57/3'4 1181535106, 114, 157 s; 242/4701, 47.08,47.09, 47.5; 28171.3

[56] References Cited UNITED STATES PATENTS 3,475,896 11/1969 Gibson eta1. ..57/106 2,976,671 3/1961 Steen i ..57/5 5.5 X 2,596,520 5/1952Barker r 242147.07 3,489,368 1/1970 Rehwald.... ZS/71.3 2,553,127 5/1951Barker "242/4719 X 3,018,608 l/1962 Kleekammetal. .....57/55.5X3,073,001 1/1963 Kroll ..28/71.3

Primary Examiner-Werner H. Schroeder Attorney-Johnston, Root, OKee'ffe,Keil, Thompson & Shuttleff 571 ABSTRACT A thread guide roller providedwith a radially 'projectingcircumferential bead intermediate the ends ofits cylindrical thread contacting surface; particularly in combinationwith a godet in draw-twist apparatus.

10 Claims, 8 Drawing Figures THREAD 1 550 MEANS THREAD TWISTING MEANSPATENTEDJAH 9 ms 3.708.969

THREAD FEED MEANS FIG. I

THREAD TWISTING MEANS INVENTORSI PETER KLEMENTZ HEINZ MASSAT CHRISTOPHNITSCHKE HERBERT HAUBOLD ATT'YS THREAD GUIDE ROLLER It is a commonpractice to conduct a thread or yarn with several windings over a threadguide roller, especially in combination with a draw godet where thewindings pass around both the godet and guide roller, e.g. as theso-called draw or stretch rolls of drawing apparatus. The individualthread windings are spatially separated along the contacting surfaces ofthe godet and guide roller, this separation being achieved in a knownmanner by the slight tilting of the axes of the godet and guide roller.Thus, the godet is normally positioned adjacent the guide roller withalmost parallel axes of rotation which form a very small anglesufficient to produce the desired effect. One attempts to maintain thisspatial separation because it is essential to avoid thread windingsrunning over one another and a resulting damage or breakage of thethreads.

If the thread or yarn which runs over the guide roller is one whichextends directly from this roller to a previous or subsequent threadtwisting device, the path of travel or run of the thread on the guideroller is extremely uneven. This arises from the fact that a twist beingformed either as a true twist or as a false twist is transmitted fromthe twisting device along the thread itself up to the guide roller wherethis twist causes the thread to roll in the direction of twist along thesurface of the roller. This movement of the thread axially of the guideroller causes it to come into contact with adjacent windings or loopsaround the guide roller and even climb over these adjacent windings soas to cause frequent damage to the filaments or breakage of the thread.Such unsatisfactory results can be observed in draw-twist apparatuswhether one is producing a true twist with a so-called ring twisteraccompanied by the formation of a thread balloon or whether one isproducing a false twist with a small twisting tube or other conventionalfalse twist device.

One object of the present invention is to provide a thread guide rollerwhich will prevent this rolling movement of threads axially of theroller under the influence of a twist imparted to the running threadjust before or after its winding or looping contact with the roller,especially in draw-twist apparatus which requires at least one suchguide roller in combination with a godet as thread drawing means.Another object of the invention is to provide a variation in theconstruction of this thread guide roller which will solve the statedproblem and which can be readily adapted to existing guide rollers.Other objects and advantages of the invention will become more apparentfrom the following detailed disclosure. I

It has now been found, in accordance with the invention, that asubstantial improvement can be achieved in avoiding thread damage duringsuch conventional thread processing by providing a thread guide rollercomprising a rotatably mountable thread-receiving cylindrical rollerhaving a circumferential bead projecting radially outwardly from itscylindrical surface adjacent the ends thereof. This roller is especiallyeffective in draw-twist apparatus where it is employed in combinationwith a godet as one element in thread drawing means, such apparatus alsoincluding thread twisting means in direct threaded connection with theguide roller such that the imparted twist is transmitted along thethread from the twisting means to the guide roller. With severalwindings transported along the surface of the guide roller, the bead issituated between the thread run-off end of the roller and the nextudjacent thread winding, i.e. between the last two windings near one endof the roller, preferably at a distance from the end of the threadcontacting surface of about 15 to 40 percent of the length of thisnormally cylindrical surface.

Specific embodiments of the invention are described in greater detailhereinafter in conjunction with the accompanying drawings in which:

FIG. 1 is a partly schematic illustration of draw-twist apparatus,including a side elevational view of a godet and the thread guide rollerof the invention;

FIG. 2 is a front elevational view of the godet and thread guide rollerof FIG. 1, another preferred arrangement of the guide roller inreference to the godet being shown in broken lines; and

FIGS. 3-8 are cross-sectional views of anumber of preferred embodimentsof the thread guide roller of the invention.

Referring first to FIGS. 1 and 2, a conventional rotatably driven godetl on axis la is positioned adjacent to the thread guide roller 2 whichis freely turnable on its axis 20 and which is provided with thecircumferential bead 3 spaced inwardly from its front or right end by adistance of about 25 percent of its length. The thread 4 extendsdownwardly from any suitable thread feeding means, for example a pair offeed rolls which may also be a godet and guide roller, to first contactthe thread guide roller 2 located laterally above the godet l. Thethread 4 then loops or winds several times around both the godet 1 androller 2, a number of these individual windings 5 lying to the left ofthe bead 3 while the last winding 6 lies to the right of this bead 3 asthe thread 4 is taken off the guide roller 2 and conducted directly to athread twisting means where an S- twist is imparted to the thread.

The S-twist imparted by the twisting device travels back to the roller 2and causes the winding 6 to roll to the left in an axial direction alongthe circumferential surface of the roller, such that the winding 6 wouldnormally roll over the windings 5. However, the bead 3 .prevents thisrolling movement, the thread winding 6 remaining in contact with theright flank of the bead 3 without climbing over this bead. In thismanner, i.e. with the bead acting as a barrier or obstacle to therolling effect of the twisted thread, damages to the thread and breakingof the thread can be completely avoided.

This first arrangement is also shown in FIG. 2 in solid lines as a frontview of the godet and guide roller of FIG. 1, i.e. where the guideroller or run-off roller 2 is positioned laterally above the godet l.The guide roller 2' is however preferably placed laterally below thegodet 1 (as shown in broken lines), especially where these two membersserve as the draw rolls in the drawtwist apparatus with a generallyvertical path of travel of the yarn or thread 4. In this latter case,the highly tensioned thread 4' as it is transported approximatelyvertically downwardly from a feed godet or similar feed means runslaterally in close proximity to the draw godet 1 without touching thisgodet and then first contacts the guide roller 2' which is approximatelytangent to the vertical path of thread travel. Thereafter, the

thread is wound in running contact several times around both the godet land roller 2' to form a number of spaced loops in the same manner asshown in FIG. 1. Again, thelast winding 6 is to the right of the bead 3'and runs off from this position, again in an approximately vertical pathto the thread twisting means.

The bead 3' on guide roller 2' as shown in FIG. 2 also prevents therolling movement of the last winding over the remaining windings 5 justas in the embodiment of FIG. 1. Itis further important, however, toavoid thread Thus, where the most strongly tensioned thread lies abovethe guide roller 2' as shown by broken lines in,

FIG. 2, i.e. where the thread is being drawn or stretched, it isadvisable to'position the godet l laterally above this roller 2' andclose to the upper more strongly tensioned thread 4' as it comes ontothe guide roller. Viewed in terms of the approximately vertical path ofthe thread 4', the thread length under higher tension-passes downwardlyclose by to the godet l and past this godet onto the guide roller 2'placed laterally beneath thegodet. Then, the thread continues throughseveral loops or windings under essentially slighterten sion around boththe godet and roller, the last winding being held :in place by the bead3', before it again resumes an approximately vertical direction oftravel as it runs off of the roller 2' down to a ring-twist spindle orsimilar twisting means. This arrangement has the additional effect'ofproviding a maximum surface contact of the thread 4' as it is firstbrought onto the godet/roller combination, i.e. with reference to itsinitial contact with the roller 2. At the same time, the last winding 6as it runs off the godet/roller combination has a minimum of contactwith the cylindrical surface of the guide roller 2' while beingmaintained axially of this I roller by the bead 3'. In this manner,breaking or other damage to the thread is most extensively avoided whileensuring the uniform running and even spacing of the windings on thegodet/roller combination without any axial thread rolling movement overlong periods of continuous operation. I

The individual beads 3 (or 3') can be integral with the guide roller 2as shown in FIG. 3. However, in order to equip existingthread guiderollers with a supplemental bead as required by theinvention, it ispossible to construct the bead separately as a ring-shaped member whichcan then be pressed, shrink-fitted or otherwise drawn or forced onto theexisting roller in closely, fitting contact with the thread contactingsurface of the roller, i.g; as shown by the ring bead 3a in FIG. 5. Suchthe particular bead 3b or 30 is integral with a shell or sleeve 7capable of being slipped onto the roller 2 such that this sleeveprovides the thread contacting-surface of the guide roller. This sleeve7 is especially adapted to be removably mounted, e.g. with radialtightening screws or other means of holding it firmly onto the roller 2.However, the annular ring member 30 as shown in FIG. 5 can also beremovably mounted, e.g. by screws extending radially through its apex,and can be easilyslipped along the roller 2 so as to adapt the roller toany specific operation or different thread runoff configurationsrequiring one or several windings. This ring member therefore representsan especially economical embodiment of the invention for reequippingexisting guide rollers.

It has been found to be quite satisfactory to employ beads having anapproximately triangular cross-section as indicated in FIGS; 3, 4 and 5,especially with a flattened or rounded apex, e.g. as with anapproximately trapezoidal cross-section as suggested by FIG. 6. Othershapes are also feasible, depending upon the desired anti-rolling-effectto be achieved. In all cases, the flanks on either side of the beadshould form an obtuse angle with the thread contacting surface of theroller.

In order to prevent a severe rolling effect in difficulty supportedthreads having a very strong twist, it is further recommended that thebead be constructed with concave oppositely disposed flanks runningsmoothly into the thread contacting surface of the cylindrical roller,i.e. substantially as illustrated by the embodiment of FIG. 6'. With thegradually increased slope or inclination of the flank facing the lastrunoff winding, the upward climbing movement of the thread i as it isrolled axially by the twist is completely stopped.

One can further increase this rounded concave shape of the flank ratherthan providing a reverse curve over the top of the bead, FIG. 7,respectively the ring bead may even be given a circular orovalcross-section, FIG.

8, thereby avoiding any possibility of the thread riding up over thebead.

' The minimum height of the bead, i.e. in its radial direction outwardlyfrom the cylindrical roller surface, can be easily determined for anyoperationby a few routine tests. This height should ordinarily be atleast five times and preferably many more times the diameter of thethread or yarn being transported, again dependingupon its precisecross-sectional shape or configuration.

If the bead is installed as a ring member or as part of a sleeve slippedonto the original guide roller, it is the cylindrical thread contactingroller is composed of a hard surfaced metal or ceramic material. Thebead material should be very smooth so that the thread or yarn does notdiscover a holding position or stairstep indentation which wouldencourage a rolling combing movement.

When employing a simple thread guide roller without severalwindingsalong its length,it is possible to locate the bead at about thecenter of the roller. Depending upon the direction of thread twist,i.e'. either an S-twist the roller and repeating this path several timesin a spiral or helical type of winding. Since the godet is normally oflarger diameter than the guide roller, larger loops are formed on thegodet than the roller as indicated in the drawings, and if desired, thegodet may be heated for treatment of the transported thread at anelevated temperature. In this case,'the bead is best located about to 40percent of the length of the guide roller from the run-off end,preferably about to percent from this end.

The multi-looped winding of the godet/roller combination is particularlydesirable in a draw-twist apparatus where the thread is first drawn orstretched, i.e. between a first driven godet/lroller pair acting as feedrolls and a second driven godet/roller pair acting as the draw rolls,the latter pair of rolls turning at a higher rotational speed than thefirst set of feed rolls to impart a predetermined stretching to thethread under relatively high tension. Twist is then immediately impartedto the stretched thread after it leaves the draw rolls, it beingessential for purposes of the invention to provide a beaded guidedroller as described herein as a means of counteracting the rollingmovement of the thread along this guide roller of the draw rolls. Thetwisted thread can then be taken up on a spindle or supply bobbin whilesubstantially avoiding or completely preventing thread breakage anddamage to the thread, yarn or individual filaments during the draw-twistoperation.

The beaded thread guide roller ofthe invention is not only successful incounteracting the axially directed rolling movement of a twisted threadalong the roller surface but also eliminates any necessity forinstalling so-called twist stoppers or other complicated devices betweenthe twisting device and the guide roller of the drawing means, suchdevices being only partly effective in preventing a twist from beingcarried back to the guide roller. This in turn permits a relativelyshort span between this guide roller and the twisting device with acorresponding reduction in the overall effective operating length of thedraw-twist apparatus in the usually vertical direction of thread travel.

Other similar thread processing operations requiring a thread guideroller to be used with a thread having an applied twist or torquecausing the undesired rolling movement may also be substantiallyimproved by employing the beaded roller of the invention, e.g. whetherthe twist is communicated forwardly along the thread as it is first runon the guide roller or backwardly along the thread as it is run off thelast winding on the guide roller. The latter arrangement is much morecommon in draw-twist apparatus whereas the former arrangement is morelikely to be used where the draw rolls receive a twisted thread for heattreatment, e.g. in fixing a thread which has been false twisted on aheated godet.

These and other variations of the overall apparatus will be readilyapparent to those skilled in this art since one can employ quiteconventional apparatus for different thread treating operations whilesimply inco'rporating the essential beaded guide roller of theinvention. Accordingly, the invention is not limited to the specificembodiments of apparatus illustrated herein except to the extentdesignated by the spirit and scope of the accompanying claims.

The invention is hereby claimed as follows:

1. ln draw-twist apparatus having thread feed means and drawing meansincluding a godet rotatable on its axis in combination with an adjacentthread guide roller which is freely turnable on an axis slightly tiltedwith reference to the godet axis to receive and advance a tensionedthread in running contact with spatially separated thread windingspassing around both said godet and roller and also having threadtwisting means to receive and impart a twist to the thread immediatelyfollowing said drawing means such that twist is transmitted along thethread extending from said twisting means back to said godet and guideroller, the improvement of a thread guide roller positioned as means toreceive the thread which is more strongly tensioned directly from saidfeed means and as means to extend the less strongly tensioned threaddirectly to said twisting means, said thread guide roller having anelongated cylindrical thread contacting surface of constant radius witha single circumferential bead projecting radially from said surfaceintermediate the ends thereof to prevent the imparted twist of the lessstrongly tensional thread extension from causing a rolling back of thethread axially along the roller.

2. Draw-twist apparatus as claimed in claim 1" wherein saidcircumferential bead is located on said thread guide roller at adistance from one end thereof of about 15 to 40 percent of the length ofsaid thread contacting surface.

3. Draw-twist apparatus as claimed in claim 1 wherein saidcircumferential bead is a ring-shaped member constructed separately fromsaid roller and forced onto said roller in closely fitting contact withsaid thread contacting surface.

4. Draw-twist apparatus as claimed in claim 1 wherein saidcircumferential bead is located on a cylindrical annular sleeve slippedonto a roller, said sleeve providing a thread contacting surface on eachside of said bead.

5. Draw-twist apparatus as claimed in claim 4 wherein saidcircumferential bead is located ata distance from one end of said sleeveof about 15 to 40 percent of the sleeve length.

6. Draw-twist apparatus as claimed in claim 1 wherein saidcircumferential bead consists of a wearresistant plastic material whilethe remaining thread contacting surface is composed of a hard-surfacedmetallic or ceramic material.

7. Draw-twist apparatus as claimed in claim 1 wherein saidcircumferential bead has an approximately triangular to trapezoidalcross-section with oppositely disposed flanks forming an obtuse anglewith the thread contacting surface of the said roller.

8. Draw-twist apparatus as claimed in claim 1 wherein saidcircumferential bead has a rounded triangular to trapezoidalcross-section with oppositely disposed flanks providing a smooth'roundedconcave surface with the thread contacting surface of said roller.

9. Draw-twist apparatus as claimed in claim 1 v wherein said threadguide roller is arranged approxione side thereof in close proximity tothe more strongly tensioned thread length extending from said guide j'roller.

10. Draw-twist apparatus as claimed in claim 1 wherein said threaddrawing meansincludes an upper ,feed means and lower drawwrollsconsisting of said godet in combination with said guide roller, and saidthread twisting means is positioned below said lower I draw rolls toprovidea substantially vertical linear path of thread travel from saidupper feed means to said guide roller and again from said guide rollerto said twisting means, the thread being wound a number of timesaroundboth said godet and said guide roller, and

said godet is arranged laterally above said guide roller 7 in closeproximity to said first-mentioned substantially vertical linear path ofthread travel from said upper feed means to said guide roller. I

PO-1O5O UNITED STATES EXTENT @FFECE (5/69) i t I v o I QERTIFICATE OFCOECEK Inventor) Peter Klementz et a1 It is certified that error appearsin the :aboveddentified patent and that said Letters Patent are herebycorrected as shown below:

I" 1 First page, left-hand column, eighth line, insert [75 Assignee:Akzona Incorporated, Asheville,

North Carolina Column 5, line "lopped" should read looped Signed endsealed this 29th day of January 1974.

(SEAL) Attest:

EDWARD M.PLETCHE R,JR. RENE D. TEGTMEYER Attesting Officer ActingCommisioner ofPatents

1. In draw-twist apparatus having thread feed means and drawing meansincluding a godet rotatable on its axis in combination with an adjacentthread guide roller which is freely turnable on an axis slightly tiltedwith reference to the godet axis to receive and advance a tensionedthread in running contact with spatially separated thread windingspassing around both said godet and roller and also having threadtwisting means to receive and impart a twist to the thread immediatelyfollowing said drawing means such that twist is transmitted along thethread extending from said twisting means back to said godet and guideroller, the improvement of a thread guide roller positioned as means toreceive the thread which is more strongly tensioned directly from saidfeed means and as means to extend the less strongly tensioned threaddirectly to said twisting means, said thread guide roller having anelongated cylindrical thread contacting surface of constant radius witha single circumferential bead projecting radially from said surfaceintermediate the ends thereof to prevent the imparted twisT of the lessstrongly tensional thread extension from causing a rolling back of thethread axially along the roller.
 2. Draw-twist apparatus as claimed inclaim 1 wherein said circumferential bead is located on said threadguide roller at a distance from one end thereof of about 15 to 40percent of the length of said thread contacting surface.
 3. Draw-twistapparatus as claimed in claim 1 wherein said circumferential bead is aring-shaped member constructed separately from said roller and forcedonto said roller in closely fitting contact with said thread contactingsurface.
 4. Draw-twist apparatus as claimed in claim 1 wherein saidcircumferential bead is located on a cylindrical annular sleeve slippedonto a roller, said sleeve providing a thread contacting surface on eachside of said bead.
 5. Draw-twist apparatus as claimed in claim 4 whereinsaid circumferential bead is located at a distance from one end of saidsleeve of about 15 to 40 percent of the sleeve length.
 6. Draw-twistapparatus as claimed in claim 1 wherein said circumferential beadconsists of a wear-resistant plastic material while the remaining threadcontacting surface is composed of a hard-surfaced metallic or ceramicmaterial.
 7. Draw-twist apparatus as claimed in claim 1 wherein saidcircumferential bead has an approximately triangular to trapezoidalcross-section with oppositely disposed flanks forming an obtuse anglewith the thread contacting surface of the said roller.
 8. Draw-twistapparatus as claimed in claim 1 wherein said circumferential bead has arounded triangular to trapezoidal cross-section with oppositely disposedflanks providing a smooth rounded concave surface with the threadcontacting surface of said roller.
 9. Draw-twist apparatus as claimed inclaim 1 wherein said thread guide roller is arranged approximatelytangent to the linear path of the thread being drawn between feed anddraw means with the thread extending from said guide roller in onelength which is more strongly tensioned, then passing around both saidgodet and guide roller and finally from said guide roller in anotherlength which is less strongly tensioned, and said godet is arrangedlaterally of said guide roller on one side thereof in close proximity tothe more strongly tensioned thread length extending from said guideroller.
 10. Draw-twist apparatus as claimed in claim 1 wherein saidthread drawing means includes an upper feed means and lower draw rollsconsisting of said godet in combination with said guide roller, and saidthread twisting means is positioned below said lower draw rolls toprovide a substantially vertical linear path of thread travel from saidupper feed means to said guide roller and again from said guide rollerto said twisting means, the thread being wound a number of times aroundboth said godet and said guide roller, and said godet is arrangedlaterally above said guide roller in close proximity to saidfirst-mentioned substantially vertical linear path of thread travel fromsaid upper feed means to said guide roller.